The present invention relates to a portable data-processing device.
Portable data processing devices such as cellular telephones have become ubiquitous due to the ease of use and the instant accessibility that the phones provide. For example, modern cellular phones provide calendar, contact, email, and Internet access functionalities that used to be provided by desktop computers. For providing typical telephone calling function, the cellular phone only needs a numerical keyboard and a small display. However, for advanced functionalities such as email or Internet access, full alphanumeric keyboards are desirable to enter text. Additionally, a large display is desirable for readability. However, such desirable features are at odds with the small size of the cellular phone.
Additionally, as the cellular phone takes over functions normally done by desktop computers, they carry sensitive data such as telephone directory, bank account and brokerage account information, credit card information, sensitive electronic mails (emails) and other personally identifiable information. The sensitive data needs to be properly secured. Yet, security and ease of use are requirements that are also at odds with each other.